In 2011, we accrued several new FHLH patients to our study, after validating their lack of known mutations and the normal expression of various candidate genes. While continuing to accrue additional patients, we have initiated exome sequencing on these samples, with the goal of identifying new mutations responsible for disease. We have obtained a partial list of candidate genes, which we are now attempting to winnow down by functional evaluations in vitro. In parallel, we have also prepared keratinocyte cultures from skin biopsies to improve the efficiency of generating induced pluripotent stem cells from normal healthy volunteers and patients.